CareerCup

for case 1 the answer is pretty simple and straightforward: Use mergesort...

what about case 2 ?
can you explain your approach to case 1.

add the element using binary search ...........may be it might not efficient solution.

list one 2 8 5 10
list two 12 5 78 34
take 2,12 compare add so 2, 12
next compare 8,5 and use binary search to add this elements
2 5 8 12 .....

Are we sure this is an algorithmic question ? May be *nix Operating systems may come handy with its paste and/or join & sort commands. Any suggestions ?

1. For case 2, Read all the words into an array
2. Sort the array using quick sort
3. Open a handler to empty file 3, Read words sequentially from file 1.
4. Locate the word using binary search in the sorted array.
5. Copy the line from the file and write it into file 3 at line = array index. i.e if the word is found at array index 25, the line read from file must be written at the 25th line in file 3.

thanx for description of an algo

Since they are large files there are chances that all the words itself dont fit into memory. So for case 1 you would do just a external merge while for case 2 you would do an external merge sort with the word as the key.

yes we have to use external sort , which divides data in chunks sort it and finally merges it. refer wiki